SAN FRANCISCO (Reuters) - Some San
Francisco-area residents are flush with cash, thanks to an anonymous
donor who has been hiding envelopes full of money in secret spots around
the city.

The donor has been conducting the Northern California treasure
hunt by posting clues to a Twitter account called HiddenCash,
sending followers to uncover envelopes filled with about $100 taped
behind stop signs, bulldozers, fire hydrants and dumpsters.

By late Wednesday, more than 190,000 people were following the
Twitter account.

The donor describes the five-day-old game as way to give back to
society after making millions in the city's real estate market.

"I want the spotlight on what I'm doing and trying to do," he told
CNN. "I have no plans to stop anytime soon. I'm planning to continue
this indefinitely into the future."

The donor has encouraged winners to tweet photos of their winnings.
So far, the experiment has appeared to be a success.

A local television web producer treated co-workers to pizza, while
another donated the cash to San Francisco's St. Anne's church and
another to the Muttville Senior Dog Rescue, according to postings on
Twitter.

Deidre Washington, 35, of Oakland, said in a phone interview that
she and her 14-year-old daughter used a Twitter clue to hunt down an
envelope taped to a parking meter in San Francisco's Mission
district with $60 inside.

Washington said she split the contents with several homeless people
at a camp nearby. "We're always trying to give back," she said.

The pair then doubled their winnings after following a second tweet
to another $60 envelope at Burger King.

"We split it - she's using it for the summer and I got some gas,"
Washington said of herself and her daughter.